Buggy code:
public int getTextLimit ( ) { } public int getVisibleItemCount ( ) { } boolean hasFocus ( ) { } public int indexOf ( String string ) { } public int indexOf ( String string , int start ) { } int mbcsToWcsPos ( int mbcsPos ) { } public void paste ( ) { } void register ( ) { } public void remove ( int index ) { } public void remove ( int start , int end ) { } public void remove ( String string ) { } public void removeAll ( ) { } public void removeModifyListener ( ModifyListener listener ) { } public void removeSelectionListener ( SelectionListener listener ) { } public void removeVerifyListener ( VerifyListener listener ) { } boolean sendKeyEvent ( int type , int msg , int wParam , int lParam , Event event ) { } public void select ( int index ) { } void setBackgroundImage ( int hBitmap ) { } void setBackgroundPixel ( int pixel ) { } void setBounds ( int x , int y , int width , int height , int flags ) { } public void setFont ( Font font ) { } void setForegroundPixel ( int pixel ) { } public void setItem ( int index , String string ) { } public void setItems ( String [ ] items ) { } public void setOrientation ( int orientation ) { } void setScrollWidth ( ) { } void setScrollWidth ( int scrollWidth ) { } void setScrollWidth ( TCHAR buffer , boolean grow ) { } void setScrollWidth ( int newWidth , boolean grow ) { } public void setSelection ( Point selection ) { } public void setText ( String string ) { } public void setTextLimit ( int limit ) { } void setToolTipText ( Shell shell , String string ) { } public void setVisibleItemCount ( int count ) { } void subclass ( ) { } boolean translateTraversal ( MSG msg ) { } boolean traverseEscape ( ) { } void unsubclass ( ) { } String verifyText ( String string , int start , int end , Event keyEvent ) { } int wcsToMbcsPos ( int wcsPos ) { } int widgetExtStyle ( ) { } int widgetStyle ( ) { } TCHAR windowClass ( ) { } int windowProc ( ) { } int windowProc ( int hwnd , int msg , int wParam , int lParam ) { } LRESULT WM_CTLCOLOR ( int wParam , int lParam ) { } LRESULT WM_GETDLGCODE ( int wParam , int lParam ) { } LRESULT WM_KILLFOCUS ( int wParam , int lParam ) { } LRESULT WM_LBUTTONDOWN ( int wParam , int lParam ) { } LRESULT WM_SETFOCUS ( int wParam , int lParam ) { } LRESULT WM_SIZE ( int wParam , int lParam ) { if ( ( ( style ) & ( SWT . SIMPLE ) ) != 0 ) { LRESULT result = super . WM_SIZE ( wParam , lParam ) ; if ( OS . IsWindowVisible ( handle ) ) { if ( OS . IsWinCE ) { int hwndText = OS . GetDlgItem ( handle , Combo . CBID_EDIT ) ; if ( hwndText != 0 ) OS . InvalidateRect ( hwndText , null , true ) ; int hwndList = OS . GetDlgItem ( handle , Combo . CBID_LIST ) ; if ( hwndList != 0 ) OS . InvalidateRect ( hwndList , null , true ) ; } else { int uFlags = ( ( OS . RDW_ERASE ) | ( OS . RDW_INVALIDATE ) ) | ( OS . RDW_ALLCHILDREN ) ; OS . RedrawWindow ( handle , null , 0 , uFlags ) ; } } return result ; } LRESULT result = null ; <START_BUG> if ( ( ( ( style ) & ( SWT . READ_ONLY ) ) != 0 ) || ( ( ( style ) & ( SWT . DROP_DOWN ) ) == 0 ) ) { <END_BUG> result = super . WM_SIZE ( wParam , lParam ) ; } else { int index = OS . SendMessage ( handle , CB_GETCURSEL , 0 , 0 ) ; boolean redraw = false ; TCHAR buffer = null ; int [ ] start = null ; int [ ] end = null ; if ( index == ( OS . CB_ERR ) ) { int length = OS . GetWindowTextLength ( handle ) ; if ( length != 0 ) { buffer = new TCHAR ( getCodePage ( ) , ( length + 1 ) ) ; OS . GetWindowText ( handle , buffer , ( length + 1 ) ) ; start = new int [ 1 ] ; end = new int [ 1 ] ; OS . SendMessage ( handle , CB_GETEDITSEL , start , end ) ; redraw = ( ( drawCount ) == 0 ) && ( OS . IsWindowVisible ( handle ) ) ; if ( redraw ) setRedraw ( false ) ; } } result = super . WM_SIZE ( wParam , lParam ) ; if ( isDisposed ( ) ) return result ; if ( buffer != null ) { OS . SetWindowText ( handle , buffer ) ; int bits = ( start [ 0 ] ) | ( ( end [ 0 ] ) << 16 ) ; OS . SendMessage ( handle , CB_SETEDITSEL , 0 , bits ) ; if ( redraw ) setRedraw ( true ) ; } } if ( ( ( style ) & ( SWT . H_SCROLL ) ) != 0 ) setScrollWidth ( scrollWidth ) ; return result ; } LRESULT wmChar ( int hwnd , int wParam , int lParam ) { } LRESULT wmClipboard ( int hwndText , int msg , int wParam , int lParam ) { } LRESULT wmCommandChild ( int wParam , int lParam ) { }

Fix:
if ( ( ( style ) & ( SWT . READ_ONLY ) ) != 0 ) {